OBDEB OF CHEIBOPTEBA. 
The Cheiroptera are those singular animals commonly desig- 
nated by the name of Bats. For a long time, and even nowa- 
days, people have entertained the most erroneous ideas with 
regard to these odd creatures. Aristotle defined them as Birds 
with wings of skin. After him Pliny, Aldrovandus, and Scaliger, 
fell into the same error. The Bats, however, have no other 
resemblance to Birds than being able to fly. 
At last, after many centuries, the different characters that fix 
the rank of these animals in the scale of created beings are known 
even to the minutest details, removing all doubts of their not 
belonging to the Mammalia. 
The altogether peculiar conformation of their anterior limbs, 
and the transformation of their hands into wings, constitute 
for them a character which is perfectly distinctive from other 
Mammalia. Their scientific denomination also marks this special 
organic disposition. The word Cheiroptera signifies “ winged 
hand,” or “hand transformed into a wing” (x et P, hand, nTepov, 
wing). The Cheiroptera are, therefore, Mammals with “winged 
hands.” 
How has nature formed this type P All the fingers of the 
hand, with the exception of the thumb, which is short, has 
a nail, and is quite free, are immoderately long, and united 
by means of a transparent membrane, which is without hair. 
This membrane covers also the arm and fore- arm, and is nothing 
else than a prolongation of the skin of the flanks. It is composed 
of two very thin layers, one a continuation of the integuments 
of the back, the other that of the abdomen. It also extends 
between the posterior limbs, where it is more or less developed, 
according to the species, and there takes the name of the inter- 
